title: Pesticide residues in river sediments from the Pantanal Wetland, Brazil.
abstract: Sediment samples from 25 sites in 17 rivers of the Pantanal (Brazil) were analyzed with the objective of evaluating pesticide contamination in sediments. Samples were extracted with an acetone, ethylacetate, and water mixture 2:2:1 (v/v/v). The extract was purified by flash chromatography with aluminum oxide and florisil. A multiresidue gas chromatography-mass spectrometry method was applied to monitor 23 pesticides of different chemical classes (organochlorine, organophosphorus, triazines, anilides and pyrethroids) with some of their degradation products. Compounds identified in sediment samples included lambda -cyhalothrin (1.0 to 5.0 micro g kg(- 1)), p,p'-DDT (3.6 micro g kg(- 1)), deltamethrin (20.0 micro g kg(- 1)) and permethrin (1.0 to 7.0 micro g kg(- 1)).
authors.affiliation: Grupo de Analise Instrumental Aplicada, Universidade Federal de Sao Carlos, Sao Carlos, SP, Brazil. kelbermiranda@hotmail.com
authors.forename: Kelber
authors.initials: K
authors.lastname: Miranda
authors.forename: Marcelo L F
authors.initials: ML
authors.lastname: Cunha
authors.forename: Eliana F G C
authors.initials: EF
authors.lastname: Dores
authors.forename: Debora F
authors.initials: DF
authors.lastname: Calheiros
mesh_terms: D001938:Brazil; D002849:Chromatography, Gas / Q000379:methods; D019015:Geologic Sediments / Q000737:chemistry*; D010573:Pesticide Residues / Q000032:analysis*; D045483:Rivers / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D010573:Pesticide Residues; D014874:Water Pollutants, Chemical